Method and apparatus for simultaneously assembling a plurality of tires

ABSTRACT

A tire assembly method and apparatus are disclosed which utilize at least two rotatable turrets (16, 18) that each have two drums (26, 28, 58, 60) and at least one transfer unit (156) for transferring tire components from one turret to another. The preferred embodiment of the invention features three turrets (16, 18, 20) and two transfer units (156, 170), wherein a carcass band is assembled on the drums of a first turret (16) the tread package is assembled on a third turret (20), and the complete tire carcass is assembled on a second turret (18), in between the first and third turrets. Simultaneous, continuous and sequential building and assembly of tire carcass bands and tread packages for a plurality of tires is provided by the method and apparatus of this invention.

TECHNICAL FIELD

This invention pertains to the art of methods and apparatuses forassembling tires, and more specifically to methods and apparatuses forsimultaneously and sequentially assembling a plurality of tires.

BACKGROUND ART

In the past, machines to build tires have included combinations of drumsfor forming tire carcasses and transfer units for transferring partiallybuilt tire carcasses from drum to drum. One such tire building apparatusis disclosed in U.S. Pat. No. 5,141,587 to Sumiuchi et al. Sumiuchiutilizes three drums for forming green partially built carcasses andtransfer units that slide along guide rails for transferring thepartially built carcasses from one drum to another. At any given time,tire components can be applied to the partially built carcasses of threetires. Applicants recognized the need to increase the efficiency andproduction of tire building apparatuses. Applicants utilize a number ofrotating turrets to successionally move tire forming drums fromcomponent applicator to component applicator without having to transfera partially formed tire carcass from a drum more than once, therebyreducing the time to produce tires while providing tire uniformity andproduction efficiency.

The present invention contemplates a new and improved tire buildingapparatus and method which is simple in design, effective in use, andovercomes the foregoing difficulties and others while providing betterand more advantageous overall results.

DISCLOSURE OF INVENTION

In accordance with the present invention, a new and improved tirebuilding apparatus and method is provided which increases tire buildingefficiency and uniformity while reducing production time.

According to one aspect of the present invention a tire buildingapparatus is disclosed, the tire having a plurality of associated tirecomponents. The tire building apparatus for assembling the plurality oftire components includes at least two turrets, each of the turrets beingrotatable about a generally horizontal axis, drum shafts extending fromeach of the turrets in generally opposite directions, drums mounted onthe drum shafts, the turrets and the drum shafts being in generalalignment with one another along an axis extending between the turrets,tire component application means positioned adjacent the drums forapplying the associated tire components to the drums to form a tirecarcass band, at least one transfer unit located between the turrets fortransferring the tire carcass band from one of the drums of one of theturrets to one of the drums of the other of the turrets, and tireremoval means for removing the tire carcass from the tire buildingapparatus.

According to another aspect of the present invention, there is provideda tire building apparatus for assembling a plurality of associated tirecomponents to form a tire carcass including a first turret having afirst drum shaft and a second drum shaft extending from the first turretin opposite directions, the first drum shaft having a first drum mountedthereon, the second drum shaft having a second drum mounted thereon andthe first turret being rotatable to move the first drum and the seconddrum between a first station and a second station; the second turrethaving a third drum shaft and a fourth drum shaft extending from thesecond turret in opposite directions, the third drum having a third drummounted thereon, the fourth drum shaft having a fourth drum mountedthereon and the second turret being rotatable to move the third drum andthe fourth drum between a third station and a fourth station; the thirdturret having a fifth drum shaft and a sixth drum shaft extending fromthe third turret in opposite direction, the fifth drum shaft having afifth drum mounted thereon, the sixth drum shaft having a sixth drummounted thereon; and the third turret being rotatable to move the fifthdrum and the sixth drum between a fifth station and a sixth station;means for applying tire components to the first drum and the second drumat the first station; means for applying tire components to the firstdrum and the second drum at the second station; means for applying tirecomponents to the fifth drum and the sixth drum at the fifth station;means for applying tire components to the fifth drum and the sixth drumat the sixth station; a first transfer unit located between the firstturret and the second turret for transferring applied tire componentsfrom the first station of the first turret to the third station of thesecond turret; means for applying beads to the applied tire componentsduring transfer between the first station and the third station; asecond transfer unit located between the second turret and the thirdturret for transferring applied tire components from the fifth stationof the third turret to the fourth station of the second turret toassemble a tire carcass; and tire carcass removal means for unloadingthe tire carcass.

According to another aspect of the present invention, there is provideda method of building a tire using a tire building apparatus having afirst turret spaced from a second turret, a transfer unit positionedbetween the first turret and the second turret, the first turret havinga first drum and a second drum, the second turret having a third drumand a fourth drum, a first station and a second station located at thefirst turret for positioning the first drum and the second drum adjacenttire component applicators, a third and a fourth station located at thesecond turret for positioning the third drum and the fourth drum toreceive a carcass band from the transfer unit and other tire components.The method includes the steps of positioning the first drum in the firstposition; applying a first position tire component to the first drum;rotating the first turret to move the first drum to the second position;applying a second position tire component to the first drum to form atire band; rotating the first turret to move the first drum and the tireband to the first position; transferring the tire band from the firstdrum to the third drum at the third station by the transfer unit andapplying beads to the tire band; rotating the second turret to move thethird drum to the fourth position; applying additional tire componentsat the fourth position to form a tire carcass; rotating the secondturret to move the third drum from the fourth position to the thirdposition, and removing the tire carcass from the third drum for transferto storage or vulcanization facilities.

One advantage of the present invention is that five tires may beassembled simultaneously.

Another advantage of the present invention is that a partially builtcarcass is transferred from one drum to another drum only once.

Another advantage of the present invention is that the tire buildingapparatus can produce a tire ready for vulcanization approximately every35-40 seconds.

Another advantage is that the layout of the tire component applicatorsprovides ready access for changing the applicators for building tireswith different specifications and for servicing.

Still other benefits and advantages of the invention will becomeapparent to those skilled in the art to which it pertains upon a readingand understanding of the following detailed specification.

BRIEF DESCRIPTION OF DRAWINGS

The invention may take physical form in certain parts and arrangement ofparts, a preferred embodiment of which will be described in detail inthis specification and illustrated in the accompanying drawings whichform a part hereof and herein;

FIG. 1 is a schematic plan view of a tire building apparatus;

FIG. 2 is a front view of a transfer unit;

FIG. 3 is a side view of the tire building apparatus showing the firststep in tire building procedure;

FIG. 4 is a side view of the tire building apparatus showing the secondstep in tire building procedure;

FIG. 5 is a side view of the tire building apparatus showing the thirdstep in tire building procedure;

FIG. 6 is a side view of the tire building apparatus showing the fourthstep in tire building procedure;

FIG. 7 is a side view of the tire building apparatus showing the fifthstep in tire building procedure;

FIG. 8 is a side view of the tire building apparatus showing the sixthstep in tire building procedure;

FIG. 9 is a side view of the tire building apparatus showing the seventhstep in the tire building procedure; and,

FIG. 10 is a plan view of a modification including an injection moldedtread pick-up apparatus for applying an injection molded tread to beused in conjunction with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings wherein the showings are for purposes ofillustrating a preferred embodiment of the invention only and not forpurposes of limiting the same, FIG. 1 shows a plan view of a tirebuilding apparatus 10. The tire building apparatus 10 is designed tobuild a number of tires simultaneously in a step-by-step process.Preferably, the tire building apparatus 10 partially builds five tirecarcasses simultaneously at peak performance.

The tire building apparatus 10 has at least two turrets 16, 18 and mayinclude a third turret 20. The first turret 16 has two drum shafts 26,28 that extend from the turret in generally opposite directions. Drums34, 36 are mounted on the ends of the drum shafts 26, 28 of the firstturret 16. The first turret 16 is rotatable in a manner such that drums34, 36 rotate between a first station I and a second station II. At aninitial point of time, drum 34 is located at the first station I, whiledrum 36 is located at the second station II. When the first turret 16rotates, drum 34 moves to the second station II and drum 36 moves to thefirst station I.

The second turret 18 has two drum shafts 50, 52 that extend from theturret in generally opposite directions. Drums 58, 60 are mounted on theends of the drum shafts 50, 52 of the second turret 18. The secondturret 18 is rotatable in a manner such that drums 58, 60 are movedbetween a third station III and a fourth station IV. At an initial pointof time, drum 58 is located at the third station III, while drum 60 islocated at the fourth station IV. When the second turret 18 rotates,drum 58 is moved to the fourth station IV and drum 60 is moved to thethird station III. The first turret 16, the drum shafts 26, 28 of thefirst turret, the second turret 18, and the drum shafts 50, 52 of thesecond turret are preferably in general alignment with one another.

The third turret 20 has two drum shafts 74, 76 that extend from theturret in generally opposite directions. Drums 82, 84 are mounted on theends of the drum shafts 74, 76 of the third turret 20. The third turret20 rotates in a manner such that drums 82, 84 are moved between a fifthstation V and a sixth station VI. At an initial point in time, drum 82is located at the fifth station V, while drum 84 is located at the sixthstation VI. When the third turret 20 rotates, drum 82 is moved to thesixth station VI and drum 84 is moved to the fifth station V. The thirdturret 20 and the drum shafts 74, 76 of the third turret are preferablyin a generally axial alignment with the first turret 16 and secondturret 18.

At the first station I, there are means for applying a tire component todrums 34, 36, such as a liner by an applicator 100 that is fed by aliner conveyor 102. The first station I also has a means for applying atire component to drums 34, 36, such as a sidewall by an applicator 108that may be fed by a sidewall conveyor 110. In the preferred embodimentof the invention, the liner applicator 100 and the sidewall applicator108 are positioned on opposite sides of the axis x--x. The linerapplicator 100 first applies the liner to one of the drums 34, 36, andthen the sidewall applicator 108 applies the sidewalls.

At the second station II there is located toeguard applying means suchas toeguard applicator 116 for applying a toeguard to the drums 34, 36.Also, means for applying other tire components such as plies and a wedgeto the drums, by a first ply applicator 122, a second ply applicator124, and a wedge applicator 130 located at the second station II. In thepreferred embodiment of the invention, the toeguard applicator 116 andthe first ply applicator 122 are on one side of the axis x--x, and thesecond ply applicator 124 and the wedge applicator 130 are on theopposite side of the axis. The toeguard is preferably applied first atthe second station II, and then the first ply is applied. Thereafter,the second ply and the wedge are applied.

At the fifth station V there are located means for applying another tirecomponent such as a breaker to the drums 82, 84, by a first breakerapplicator 136 and a second breaker applicator 138. In the preferredembodiment of the present invention, the first breaker applicator 136 ison one side of the axis x--x, and the second breaker applicator 138 ison the opposite side of the axis x--x. Preferably, the first breaker isapplied to either of the drums 82, 84 by the first breaker applicator136, and then the second breaker is applied by the second breakerapplicator 138.

At the sixth station VI there are located means for applying additionaltire components such as a tread, by a tread applicator 144. At the sixthstation VI there may also be located means for applying other tirecomponents such as a spiral overlay, with a spiral overlay applicator150 if high-performance tires are being produced by the tire buildingapparatus 10.

With reference to FIGS. 1 and 2, a first transfer unit 156 is locatedbetween the first turret 16 and the second turret 18. The first transferunit 156 picks up the tire components after they are assembled in theform of a band 158 on one of the drums 34, 36 at the first station I andsecond station II and transfers the band from the first station I to oneof the drums 58, 60 at the third station III. The first transfer unit156 also contains a bead loading apparatus 160 for applying beads to theband 158 as the band is transferred from the first station I to thethird station III. The first transfer unit 156 preferably has acylindrical or substantially cylindrical support structure 164 fittedwith radially movable shoes 166 that grip the band 158. The supportstructure 164 is moved axially of the apparatus 10 over one o the drums34, 36 and the movable shoes 166 are moved radially inward to grip theband 158. The first transfer unit 156 then transports the band 158 fromone of the drums 34, 36 to one of the waiting drums 58, 60 at the thirdstation III, where the support structure 164 surrounds the waiting drumand places the band over the drum. The band 158 is then released by themovable shoes 166, and the first transfer unit 156 moves away from thedrum.

At the third station III, the band 158 is shaped on one of the drums 58,60 of the second turret 18 as the turret rotates the band to the fourthstation IV.

A second transfer unit 170 is located between the second turret 18 andthe third turret 20. The second transfer unit 170 is axially movable totransfer a complete breaker and tread package from the fifth station Vand to place it around the band 158 waiting at the fourth station IV.The second transfer unit 170 preferably operates in the same manner asthe first transfer unit 156 as shown in FIG. 2.

Although five tires may be build simultaneously on the tire buildingapparatus 10, FIGS. 3-9 follow the production of one tire on the tirebuilding apparatus to illustrate the timing and steps involved in theprocess. FIG. 3 shows the beginning step of tire construction on thetire building apparatus 10. First, the inner liner is applied at thefirst station I to the drum 34 by liner applicator 100. Then thesidewall is applied by sidewall applicator 108. Next, the sidewall isautomatically spliced, or in some cases manually spliced by a worker.After the sidewall is spliced, the first turret 16 is rotated moving thedrum 34 from the first station I to the second station II. Atapproximately the same time, the first breaker is applied to drum 82 atthe fifth station V of the third turret 20 by the first breakerapplicator 136. Next, the second breaker is applied on top of the firstbreaker on drum 82 by the second breaker applicator 138. After thesecond breaker is applied, the third turret 20 is rotated, moving drum82 from the fifth station V to the sixth station VI.

FIG. 4 shows the tire building apparatus 10 with drum 34 rotated to thesecond station II and drum 82 rotated to the sixth station VI. At thesecond station II, the liner is stitched. After the stitching of theliner, the toeguard is then applied by the toeguard applicator 116. Thefirst ply is then applied by the first ply applicator 122. The secondply is applied by the second ply applicator 124. Finally the wedge isapplied by the wedge applicator 133. After the wedge is applied, thefirst turret 16 is rotated, moving the drum 234 with the band 158comprised of liner, sidewall, toeguard, plies, and wedge back to thefirst station I to await transfer to the third station III. The drum 34may be expanded before or after application of any component to placethe component in tension and remove trapped air. At the sixth stationVI, the spiral overlay may be applied by the spiral overlay applicator150 on top of the breakers if required, or the drum 82 may sit idle fora period of time until a tread is applied on top of the breakers. Thetread is then applied by the tread applicator 144, and then the tread ismanually spliced if required. The third turret 20 is then rotated,moving drum 82 back to the fifth station V to await transfer to thefourth station IV.

FIG. 5 shows the first transfer unit 156 moved into position to removethe band 158 from the drum 34 and move it to the drum 58 at the thirdstation III. Beads may be applied to the band 158 at the first station Ior at the third station III by a bead loading apparatus 160 connected tothe first transfer unit 156.

FIG. 6 shows the next step of the production of a tire carcass as thesecond transfer unit 170 is moved into position to pick up the breakerand tread package from drum 82 at the fifth station V.

FIG. 7 shows the first transfer unit 156 in position to place the band158 on the drum 58 at the third station III. After the band 158 istransferred to the drum 58 at the third station III, the second turret18 is rotated, moving the drum 58 to the fourth station IV. As thesecond turret 18 is rotated, the drum 58 inflates to shape the band 158and turns up part of the band around the beads. Further turn-up may berequired as the drum 58 remains at the fourth station IV awaiting thebreaker and tread package to complete the shaping and turn-up. Astitching device of the type commonly used in the art then may be usedto stitch the sidewall.

FIG. 8 shows the second transfer unit 170 in position for placing thebreaker and tread package onto the band 158 at the fourth station IV.The second turret 18 is then rotated, moving the drum 58 back to thethird station III after the second transfer unit 170 moves back to aneutral position as shown in FIG. 9. At the third station III, thebreaker and tread package is stitched. The tire carcass, now ready to bevulcanized, is removed from the tire building apparatus 10 by a tireremover 180 at the third station III. A tire carcass is removed from thetire building apparatus 10 approximately once every 35-40 seconds.

FIG. 10 shows an alternate embodiment of the present invention where aninjection molded tread is placed directly over the breaker at the sixthstation VI. The injection molded tread either is removed from theinjector body 184 directly by a pick-up apparatus 188 or is stored andthen loaded onto the pick-up apparatus. The pick-up apparatus 188 mayuse a pick-up shoe to grasp the injection molded tread, or, as shown inFIG. 10, the pick-up apparatus may have a vacuum ring 190 that graspsand holds the injection molded tread in place. The pick-up apparatus 188then transfers the injection molded tread to the sixth station VI andplaces the tread onto the drum 82 holding the breakers. If the pick-upshoe is used in the pick-up apparatus 188, then the shoe simply releasesthe injection molded tread. If the vacuum ring 190 is used in thepick-up apparatus 188, then air in the vacuum ring is removed to createa vacuum that holds the injection molded tread in place, and the treadis removed by allowing air into the vacuum ring, thereby eliminating thevacuum and releasing the tread.

The preferred embodiments have been described, hereinabove. It will beapparent to those skilled in the art that the above methods mayincorporate changes and modifications without departing from the generalscope of this invention. It is intended to include all suchmodifications and alterations in so far as they come within the scope ofthe appended claims or the equivalents thereof.

Having thus described the invention, it is now claimed:
 1. A method ofbuilding a tire comprising the steps of:(a) providing a tire buildingapparatus (10) having a first turret (16) spaced from a second turret(18), a transfer unit (156) positioned between said first turret (16)and said second turret (18), said first turret (16) having a first drum(34) and a second drum (36), said second turret (18) having a third drum(58) and a fourth drum (60), a first station (I) and a second station(II) located at said first turret (16) for positioning said first drum(34) and said second drum (36) adjacent tire component applicators (122,124), a third station (III) and a fourth station (IV) located at saidsecond turret (18) for positioning said third drum (58) and said fourthdrum (60) to receive a carcass band from said transfer unit (156) andother tire components, a third turret (120) spaced from said secondturret (18) with a fifth drum (82) and a sixth drum (84), a fifthstation (V) and a sixth station (VI) located at said third turret (20),and a second transfer unit (170) positioned between said third turret(20) and said second turret (18); (b) positioning said first drum (34)in said first station (I); (c) applying a first station (I) tirecomponent to said first drum (34); (d) rotating said first turret (16)about a generally horizontal axis to move said first drum (34) to saidsecond position (II); (e) applying a second station (II) tire componentto said first drum (34) to form a tire band (158); (f) rotating saidfirst turret (16) about said generally horizontal axis to move saidfirst drum (34) and said tire band (158) to said first station (I); (g)transferring said tire band (158) from said first drum (34) to saidthird drum (58) at said third station (III) by said transfer unit (156)and applying beads to said tire band (158); (h) rotating said secondturret (18) about a generally horizontal axis to move said third drum(58) to said fourth station (IV); (i) applying a tire component to saidfifth drum (82) at said fifth station (V) at approximately the same timethe steps (b) through (h) are performed; (j) rotating said third turret(20) about a generally horizontal axis to move said fifth drum (82) tosaid sixth station (VI); (k) applying another tire component to saidfifth drum (82) to provide a tread breaker package; (l) rotating saidthird turret (20) about said generally horizontal axis to move saidfifth drum (82) to said fifth station (V); (m) transferring said treadbreaker package from said fifth station (V) to said fourth station (IV)of said second turret (18) by said second transfer unit (170), aftersaid second turret (18) moves said third drum (58) to said fourthstation (IV); (n) rotating said second turret (18) about said generallyhorizontal axis to move said third drum (58) from said forth station(IV) to said third station (III); (o) removing said tire carcass fromsaid third drum (58) for transfer to storage or vulcanizationfacilities; and, (p) maintaining said first drum (34), said second drum(36), said third drum (58), said fourth drum (60), said fifth drum (82)and said sixth drum (84) in general alignment along an axis through outthe time the steps (b) through (o) are performed.
 2. The method of claim1 further comprising the steps of:wherein step (c) applying a firststation (I) tire component to said first drum (34), comprises the stepof applying a plurality of first station (I) tire components to saidfirst drum (34) from both sides of said first drum (34); and, whereinstep (e) applying a second station (II) tire component to said firstdrum (34) to form a tire band (158), comprises the step of applying aplurality of second station (II) tire components to said first drum (34)to form a tire band (158) from both sides of said first drum (34). 3.The method of claim 1 wherein prior to step (g) transferring said tireband (158) from said first drum (34) to said third drum (58) at saidthird station (III) by said transfer unit (156) and applying beads tosaid tire band (158), the method comprises the step of:expanding saidthird drum (58) to shape said tire band.
 4. The method of claim 1wherein after step (c) applying a first station (I) tire component tosaid first drum (34), the method comprises the step of:applying a secondfirst station (I) tire component to said first drum (34).
 5. The methodof claim 4 wherein after step (e) applying a second station (II) tirecomponent to said first drum (34) to form a tire band (158), the methodcomprises the step of:applying a second second station (II) tirecomponent to said first drum (34) to form a tire band (158).
 6. Themethod of claim 5 wherein said first station (I) tire component and saidsecond first station (I) tire component are applied from opposite sidesof said first drum (34).
 7. The method of claim 5 wherein said secondstation (II) tire component and said second second station (II) tirecomponent are applied from opposite sides of said first drum (34). 8.The method of claim 1 wherein step (k) applying another tire componentto said fifth drum (82) to provide a tread breaker package, comprisesthe step of:applying a tire tread to said fifth drum (82) at said sixthstation (VI).
 9. The method of claim 8 wherein said tire tread is aninjection molded tread (176) and wherein prior to the step of applying atire tread to said fifth drum (82) at said sixth station (VI), themethod comprises the steps of:loading said tire tread (176) in a pick upapparatus (188); and, transferring said tire tread (176) to said sixthstation (VI) for application to said fifth drum (182).
 10. The method ofclaim 8 wherein said tire tread is an injection molded tread (176) andwherein prior to the step of applying a tire tread to said fifth drum(82) at said sixth station (VI), the method comprises the stepsof:removing said tire tread (176) directly from an injector body by apick up apparatus (188); and, transferring said tire tread (176) to saidsixth station (VI) for application to said fifth drum (182).
 11. A tirebuilding apparatus for assembling a plurality of associated tirecomponents to form a tire carcass, comprising:(a) a first turret (16), asecond turret (18), and a third turret (20), said first turret (16)rotating between a first station (I) and a second station (II), saidsecond turret (18) rotating between a third station (III) and a fourthstation (IV), and said third turret (20) rotating between a fifthstation (V) and a sixth station (VI); (b) each of said turrets (18, 19,20) being rotatable about a generally horizontal axis, drum shafts (26,28, 50, 52, 74, 76) extending from each of said turrets in generallyopposite directions, drums (34, 36, 58, 60, 82, 84) mounted on said drumshafts (26, 28, 50, 52, 74, 76), said turrets and said drum shafts beingin general alignment with one another along an axis extending betweensaid turrets (16, 18, 20); (c) tire component application meanspositioned adjacent said drums (34, 36, 58, 60) for applying saidassociated tire components to said drums to form a tire carcass band(158); (d) a first transfer unit (156) located between said first andsecond turrets (16, 18) for transferring said tire carcass band (158)from one of said drums (34, 36) of said first turret (16) to one of saiddrums (58, 60) of said second turret (18); (e) means for applying abreaker to one of said drums (82, 84) of said third turret (20) andmeans for applying a tread to said breaker forming a tread breakerpackage at one of said drums (82, 84) of said third turret (20); (f)means for applying beads to said tire band (154); (g) a second transferunit (170) for transferring said tread breaker package from said fifthstation (V) of said third turret (20) to said carcass band at saidfourth station (IV) of said second turret (18); and, (h) tire removalmeans (180) for removing said tire carcass from said tire buildingapparatus.
 12. The tire building apparatus of claim 11 wherein said tirecomponent application means comprises:means for applying a sidewall andan inner liner to one of said drums (34, 36) of said first turret (16);and, means for applying a toeguard, a first ply, a second ply and awedge to one of said drums (34, 36) of said first turret (16), saidinner liner, said sidewall, said toeguard, said first ply, said secondply, and said wedge forming said tire carcass band (158).
 13. The tirebuilding apparatus of claim 11 wherein said tire component applicationmeans comprises:means for applying an inner liner and a sidewall to oneof said drums (34, 36) at said first station (I) of said first turret(16); and, means for applying a toeguard, a first ply, a second ply, anda wedge to one of said drums (34, 36) at said second station (II) ofsaid first turret (16), said inner liner, said sidewall, said toeguard,said first ply, said second ply, and said wedge forming said tirecarcass (158).
 14. The tire building apparatus of claim 13 wherein saidtire component application means comprises:means for applying saidbreaker to one of said drums (82, 84) at said fifth station (V) of saidthird turret (20); and, means for applying said tread to one of saiddrums (82, 84) at said sixth station (VI) of said third turret (20). 15.The tire building apparatus of claim 14 wherein said tire componentapplication means further comprises:means for applying a spiral overlayto one of said drums (82, 84) at said sixth station (VI) of said thirdturret (20).